Employers have many reasons for requiring pre-employment drug testing. One of the most obvious reasons is that of safety. Those handling dangerous equipment or those who drive commercial vehicles have a greater chance of accidents or inflicting injury upon themselves or others if they are under the influence. Companies have a moral and legal obligation to ensure that their employees adhere to Federal work-safety guidelines, and pre-employment drug screenings can be an effective tool.

Insurance and health-related absences provide two more reasons for implementing pre-employment drug testing. More than 175 million Americans are enrolled in workplace group health insurance; with an average of a 30% increase in premiums in the last three years, pre-employment drug testing may be one way to cut down on costs. Studies have linked short- and long-term health problems with drug abuse. Drug abusers are more likely to develop respiratory problems and are generally more susceptible to illness. Employers often view drug abusers as irresponsible since many absences can be attributed to the after-effects of drug usage. Employee absences cost employers millions of dollars every year, and many human resource experts suggest that pre-employment drug testing can reduce these costs.

However, some groups argue that pre-employment drug testing is not an accurate way to detect the use of drugs while at work. Many drugs, such as marijuana, will remain detectable for up to three weeks after usage. Other drugs, such as cocaine, may only be present for a few days after consumption. It is often a difficult call for an employer to make but most simply make their decisions cautiously. They often view it as better to not hire someone who occasionally uses drugs than to take the risk of the person using before or during working hours.

According to the Small Business Administration, companies lose an average of $7,000 per drug-using employee per year. This figure is often enough to convince an employer to implement a standard of pre-employment drug testing. In any given year, it is estimated that nearly 50 million American workers are required to have a drug screening. Advances in medical testing have made it quick, easy and relatively inexpensive for employers who wish to use this screening process. Many employers view this is as a simple means of ensuring the well being of both their company and their customers.